The longitudinal component of the wind disturbance is represented by \(d_1(t)\) , while \(d_2(t)\)  represents the lateral component. The disturbance component \(d_3(t)\)  represents the torque due to the wind disturbances on the body of the ship and this component has the largest magnitude among all. The nature of the disturbance \(d(t)\)  is illustrated in Fig. REF . The applied feedback control \(\tilde{v}(t,\tilde{x})\)  has the same structure as (REF ) with \(k_1=k_2=0.1\) . The value of \(\Gamma \) , that characterizes the ultimate bounds for the error \(\tilde{x}\)  is chosen as \(\Gamma =0.009\) . The plot of a subset of the motion primitives associated with the nominal disturbance-free model of the ship, with various heading angles is shown in Fig. REF . The motion primitives are generated by solving (REF ) with the same discretization scheme as in [1]} using CasADi [2]} and IPOPT [3]}. The shaded region along each of the primitives represents the tubes, which are supposed to contain the actual trajectory of the ship under the effect of the wind disturbance. The initial states of the ship are chosen as \(x(0)=[50, 100, \pi /4]^T\) , \(q(0)=[v_{max},0,0]^T\) , where \(v_{max}=6\)  knots and the final states are \(x_f\hspace{-1.4457pt}=\hspace{-1.4457pt}[900, 900, \pi /2]^T\) , \(q_f\hspace{1.4457pt}=\hspace{0.72229pt}[0,0,0]^T\) . Fig REF  shows the motion of the ship from the
<FIGURE>